Embrace the light! Researchers built all-optical device for faster broadband

Our computer networks and broadband connections are reliant on both light and electronics, but a breakthrough at the University of Minnesota might help take the electrons out of the equation. A new device can use light to switch states, which could enable faster, more efficient broadband.

Researchers at the University of Minnesota have built an all-optical device that is able to flip a switch. The technology might strike many as esoteric, but getting light to change state (from on to off) based only on a signal from another light is a big deal that could pave the way for faster and more-efficient broadband networks.

At its core, the research is attempting a big change — building out communications networks that won’t need to convert information back to electronic bits. It’s all photons, no electrons. Eliminating that conversion would cut down on latency, energy and eventually cost if this research can be commercialized. Of course, today’s networking infrastructure is built around zipping electrons over copper and other conductive materials, so that would need to change, but light in the form of fiber optics is encroaching because of its greater capacity and speed.

Currently, long-haul pipes and some last-mile access networks use fiber. On those networks, the bits travel as far as possible in the form of light waves before getting converted back to electronic information to be sent further or read by the communications or data center gear. But as our computing and broadband networks become more distributed and need to share more and more information in real time, networks are getting bogged down.

That’s why startups like Lightwire (purchased by Cisco) Kotura and Luxtera are trying to build silicon photonics to bring light onto the silicon chip for faster on-chip communication. Even companies such as Plexxi are trying to bring fiber gear into the data center to add capacity and speed to scaled out networks. In broadband networks, I’ve covered the move to a terabit age, and companies from Google and Verizon to Ciena and Infinera are all delivering products and services to make that a reality.

That’s the big picture. At the micro level, this research has shown that people can build a device that allows light to interfere enough with existing light waves to allow it to change state. When an electron changes state on a chip, it’s represented as a zero or one — the basis for all of our computer programming. If light can switch physical states, then it too can store data.

Glass optical fibers carry many communication channels using different colors of light assigned to different channels. In optical cables, these different-colored light channels do not interfere with each other. This non-interference characteristic ensures the efficiency of a single optical fiber to transmit more information over very long distances. But this advantage also harbors a disadvantage. When considering computation and signal processing, optical devices could not allow the various channels of information to control each other easily…until now.

The net result is faster and more efficient networking, something we can all get behind. Eventually. Currently, the new optical-relay device operates 1 million times per second and the goal is to get it to switch states several billion times per second. However, the current device is fast enough to start using it to connect fiber networks directly to broadband radio networks without the electronic conversion. Here’s a link to the original paper published Thursday in Nature for those who want to learn more.